Scientific Reports (Jun 2022)

Salivary, serological, and cellular immune response to the CoronaVac vaccine in health care workers with or without previous COVID-19

  • Marina Mazzilli Ortega,
  • Laís Teodoro da Silva,
  • Érika Donizetti Candido,
  • Yingying Zheng,
  • Bruna Tiaki Tiyo,
  • Arthur Eduardo Fernandes Ferreira,
  • Simone Corrêa-Silva,
  • Guilherme Pereira Scagion,
  • Fabyano Bruno Leal,
  • Vanessa Nascimento Chalup,
  • Camila Araújo Valério,
  • Gabriela Justamante Händel Schmitz,
  • Carina Ceneviva,
  • Aline Pivetta Corá,
  • Alexandre de Almeida,
  • Edison Luiz Durigon,
  • Danielle Bruna Leal Oliveira,
  • Patricia Palmeira,
  • Alberto José da Silva Duarte,
  • Magda Carneiro-Sampaio,
  • Telma Miyuki Oshiro

DOI
https://doi.org/10.1038/s41598-022-14283-x
Journal volume & issue
Vol. 12, no. 1
pp. 1 – 12

Abstract

Read online

Abstract We investigated the anti-SARS-CoV-2 post-vaccine response through serum and salivary antibodies, serum antibody neutralizing activity and cellular immune response in samples from health care workers who were immunized with two doses of an inactivated virus-based vaccine (CoronaVac) who had or did not have COVID-19 previously. IgA and IgG antibodies directed at the spike protein were analysed in samples of saliva and/or serum by ELISA and/or chemiluminescence assays; the neutralizing activity of serum antibodies against reference strain B, Gamma and Delta SARS-CoV-2 variants were evaluated using a virus neutralization test and SARS-CoV-2 reactive interferon-gamma T-cell were analysed by flow cytometry. CoronaVac was able to induce serum and salivary IgG anti-spike antibodies and IFN-γ producing T cells in most individuals who had recovered from COVID-19 and/or were vaccinated. Virus neutralizing activity was observed against the ancestral strain, with a reduced response against the variants. Vaccinated individuals who had previous COVID-19 presented higher responses than vaccinated individuals for all variables analysed. Our study provides evidence that the CoronaVac vaccine was able to induce the production of specific serum and saliva antibodies, serum virus neutralizing activity and cellular immune response, which were increased in previously COVID-19-infected individuals compared to uninfected individuals.